Refrigerating apparatus



' April 2 1932- A c. SCHI CKLER 1,855,730

REFRIGERATING APPARATUS Filed June 50, 1927 I v gnmmtoz 4%; a M

Patented Apr. 26, 1932 UNITED STATES PATENT OFFICE ALBERT G. SCHICKLER, F CLEVELAND, OHIO, ASSIG-NOB TO EDMUND E. ALLYNE, OF CLEVELAND, OHIO BEFBIGERATING APPARATUS Application filed. June 80, 1927. Serial No. 202,726.

This invention relates to refrigerating systems, and particularly to absorption type systems, in which a suitable refrigerant, such as ammonia, is enerated or driven oif from a suitable abs'or ing agent, such as'water, is condensed or liquefiedand collected in an evaporator during the heating cycle, and then, during the refrigerating cycle, is gasified, returned to the boiler or still and absorbed in the absorbing agent therein. In such systems, upon cessation of the heat, it is necessary to initiate return flow of the gas from the evaporator to the still and produce and continue absorption.

The object of the present invention is to provide a simple system of this kind in which the several parts are arranged and associated in a manner to provide the necessary initial impulse to start the return flow of the gas and thus begin and thereafter continue absorption, and,moreover, a system of this kind in which all parts are so arranged as to expedite and encourage absorption.

A further object of the invention is to profrom the boiler and discharged by one path, but-upon its return is conducted to a low point in the boiler in a manner to assist in circulating the absorbing agent for initiating and continuing absorption, the absorbing agent being cooled by circulation to a cooling agent, and which also includes 9. rectifier so located as to play its part in initiating and producing absorption.

Further objects of the invention are in part obvious and in part will appear more in detail hereinafter.

The drawing illustrates, more or less conventionally, one form of system embodying the invention.

The boiler or still is indicated at 1 and may be of any suitable form heated in any suitable manner, such as by an electric current, steam coils, or by the gas burner 2 shown. The gas distilled from the boiler, is conducted by a pipe 3 from its top through a rectifier 4 and thence by a pipe 5 having an upward loop 5a to a trap 6. The rectifier is in one sense a simple form of condenser, including a jacket 7 surrounding a portion of vide a system in which the gas is distilled p the pi e 3 and provided with connections 8 throug which'a cooling agent, such as water, may be circulated.

The trap 6 includes an outer shell or casing 9 into the top of which the pipe 5 extends, its lower end being open at a low level in the trap. The trap is also connected to a return pipe 10, the open end of which is above the bottom of the pipe 5, said return pipe including a rising water sealing bend 104; communicating at its other end with a return bend or loop 11 connected to the boiler for circulating the absorbing agent for cooling purposes, as will later appear.

From. the top of the trap 6 a pipe 12 leads 5 by way of an upward loop 12a to a condenser 13, including the necessary coils or turns of pipe immersed in cooling water in a tank 14, and on the other side of the condenser a pipe 15 conducts the refrigerant, now liquefied, to the top of the evaporator, which includes a tank or reservoir 16 and a number of cooling coils 17 communicating with the bottom thereof and connected to a trap 18 draining into the ipe 15.

The loop 11 has two legs, one of which, marked 21, is exposed to the atmosphere and is not subjected to any cooling effect, so that it is maintained at about the temperature of the boiler by the heat conducted thereto along so the metal, but the other legextends to an is immersed in cooling water in the tank 20. The leg 21 is substantially vertical, but the other leg of the loop has a rapidly rising or nearly vertical portion 22 beyond which the 35 pipe is extended laterally on a more gradual incline 23, to increase the length of pipe in contact with the cooling water, and the ipe 10 communicates with this leg at the bottom of its rapidly rising portion 22.

The tra 18 is for the purpose of maintaining the c arge of useful refrigerant in the evaporator 16, but permitting return through the pipe 15 to the boiler of the weaker liquor, including any absorbing agent which 9 may find its way to the evaporator. It may be of any suitable form and for example may be of the form shown and described in either of my prior a plications for refrigerating systems, Ser. 0. 144,461, filed Oct. 27,

' 192e,? Ser. No. 148,501, filed Nov. 15, 1926,

. any suitable material, as at 19a, to permit useful refrigerant to be delivered from the tank 16 to a low point in the evaporator for evaporation therein.

The trap 6 has several purposes. It provides a return from this point in the system to the boiler through the pipe 10, permitting excess liquor to be returned to the boiler, but said return pipe 10is provided with the bend or loop 10a. The chief purpose of this loop is to form a seal and prevent possible flow of liquid through pipe 10 to the trap during the boiling operation, but nevertheless permit the trap to be located at a low level relative to the boiler. Trap 6 also serves as a means for permitting free gas flow from the top of the boiler to the evaporator during the heating cycle, but compelling the gas returned fromthe evaporator to the boiler during the refrigerating period to be introduced to the boiler below the level of liquid therein. Normally the trap 6 is filled with liquor to about the level of the open end of the pipe 10, with the lower end of pipe 5 immersed in said liquor. During the boiling operation the gas discharged from the boiler bubbles out from the lower end of pipe 5 and finds a free passage through pipe 12 to the condenser, but during the refrigerating cycle the gas returning through pipe 12 cannot return through pipe 5,except by depressing the'liquor in the trap and forcing it over to the boiler through pipe 5, and the bend 5a. of pipe 5 is made sufliciently high so that the leg of liquor thus raised forms a practical water seal, and the returning gas finds an easier path to the boiler through the pipe 10 and loop 1.

All three parts to be cooled, to wit, the rectifier, the tank 20 and the tank 14, are supplied with a cooling agent, such as water,

, which may be circulated separately and continuously through all of these parts, or in series through them, or one or more of these parts may be subjected to the cooling effect of a sufiiciently large quantity of water so that circulation is unnecessary.

In operation the gas distilled from the boiler during the heating operation is first delivered to the rectifier, where it encounters the cooling effect of the acket 7, causing condensation into liquid form of any absorbing agent, such as water, which may be carried over entrained with the gas, and such condensed liquid returns by gravity to the boiler. The gas, now partially cooled, is delivered to the trap 6 and thence to the condenser 13 where it is additionally cooled and, as the pressureincreases, is liquefied. Since the gas is partially cooled before it reaches trap 6 this trap is maintained fairly cool and does not reach the high temperature usual when the trap communicates directly with the boiler and the gas is conductedto said trap without a cooling effect, such as by a rectifier, with the obvious advantages in systems of this kind from keeping the trap cool. The liquefied refrigerant in the condenser is delivered to the evaporator through pipe'l5, the trap 18 holding in the evaporator all useful refrigerant until, at the end of the boiling period the evaporator is fully charged with useful refrigerant, although a slight quantity may also be present in the condenser. The heat is now shut off.

Condensation continues for a very brief interval, but the pressure in the condenser quickly drops to a point below which condensation cannot occur. However, for ashort period thereafter the cooling effect at both the condenser and rectifier continues to produce contraction of the gas, but because the rectifier is close to the boiler the temperature of the gas as it'reaches the rectifier from the boiler is considerably higher than is the temperature of the gas when it reaches the condenser. Therefore, there is a much greater drop in temperature of the gas at the rectifier thanat the condenser, and during the early portion of the cooling period the gas contraction at the rectifier is predominant. The rectifier therefore is at first the point of low pressure, as it were, producing a suction effect through the pipe 5 upon the trap 6 but, more important, producing a like suction effect through the pipe 3 upon the boiler. In the direction of trap 6 the eflfect is merely to raise a slight leg of liquid in the pipe 5, but in the direction of the boiler the effect is to raise the level of liquid therein, with a suction effect in the pipe 10 which completely drains said pipe of liquid until finally gas enters the loop 11 from the pipe 10. Both the liquid in said pipe which is delivered at first, the refrigerant in the condenser, and the gas which follows it, are discharged into the rapidly rising portion 22 of the cooled leg of the loop, and the rising gas bubbles initiate circulation in the loop, downwardly through the leg 21 and upwardly through the leg 22, 23. The first liquid that flows from leg 21 past the entrance at pipe 10 is relatively hot weak liquor and the bubbles rise far enough to produce active circulation. Such circulation cools the absorbing agent circulated through the loop 11 and produces absorption therein of the gas flowing from pipe 10.

The net effect of the location of the rectifier between the boiler and trap 6 and of keeping the trap 6 cooled during the boiling operation is to initiate return flow of the gas from the evaporator to the boiler very promptlyafter the heat is shut off and thereby initiate absorption, which is continued throughout the refrigerating period, and, as is usual in these systems, produces the necessary suction efi'ect to continue the flow of gas.

Of course, the rectifier serves to produce contraction of the gas for only a short period during the refrigerating part of the cycle.

Previously, the pressure in the system has dropped to the point where the cooling effect on the rectifier and condenser at the lower pressure is not suflicient to produce condensation, but by the contracting effect of the rectifier return flow has been initiated, circulation through the loop 11 has been instituted,

cooling of the boiler liquor hasbegun and I absorption is continued.

The s stem is quite simple because it is of the osci lating or intermittent cyclic type, involving but a single pipe connecting trap-6 and the evaporator. All parts of the apparatus, including all vessels for refrigerant or absorbing agent, and all conduits, are sealed as a unit with no openings to or from the atmosphere.

What I claim is:

Refrigerating apparatus, comprising a boiler-absorber provided with a return loop through which boiler li nor may be circulated into heat transfer re ation with a cooling agent, said loop having two legs, one only of which is cooled, a rectifier communicating with the space in the boiler, a liquid trap communicating with the rectifier beyond the same and having return connection to the cooled leg of said return loop, and an evaporator and a condenser beyond said trap.

In testimony whereof I hereby afiix my signature.

ALBERT G. SCHICKLER. 

